Though just a small country roughly the size of Pennsylvania, Cuba has had a remarkable ability over decades to make headlines in the United States. The recent mysterious acoustic injuries to U.S. diplomats, the easing of travel bans, Guantanamo Bay, Elian Gonzalez, the Mariel Boatlift and the Cuban Missile Crisis are but a few examples.

Far less known is the significant role Cuba played in America’s Civil War. Although ostensibly neutral in the conflict, Cuba, which lies less than 100 miles off the Florida coast, was a nest of spies for both sides, a nerve center for Confederate supply operations and the virtual headquarters of Confederate efforts to circumvent the Union blockade of Southern ports.

In the vast body of non-fiction and fiction writing about the Civil War, the story of Confederate blockade-running and Union efforts to stop it is relatively underdeveloped. Robin Lloyd, who divides his time between Camden and Chevy Chase, Maryland, richly and convincingly develops this space in “Harbor of Spies: A Novel of Historic Havana.”

As a journalist, Lloyd has covered conflicts around the world for NBC News. In writing this book, he extensively researched the connection between Havana and the Civil War, reading firsthand accounts of blockade runners, Civil War-era business documents, letters, journals and diplomatic materials.

Lloyd’s research complements his own experiences growing up on the Caribbean island of St. Croix and sailing extensively in that region. Together, they enrich his storytelling and enable him to convincingly transport the reader to a Caribbean Island more than 200 years ago. In so doing, he achieves his goal of providing “a reasonably accurate depiction of Havana as it was in 1863 at the height of the U.S. Civil War.”

Amid this tumult, we meet Everett Townsend, who has but two weeks experience as captain of the American merchant schooner Laura Ann, which is delivering a cargo of Maine lumber to Havana. Arriving after sunset, the Laura Ann must wait until sunrise to enter Havana Harbor, giving Townsend and the crew what they hope will be a restful evening before continuing their work at dawn. It’s a beautiful evening, with a gentle breeze. The beam from the lighthouse is flickering over the calm waters of Havana Harbor.

That tranquil scene abruptly changes when Townsend hears screams coming from the water and sees a person thrashing around, surrounded by the “silhouettes of a half dozen shark fins and an orgy of glimmering phosphorescent light.” Townsend rescues the man, who, it turns out, is an escapee from a notorious Cuban prison, and for reasons Townsend can’t really explain, he hides the escapee from a Spanish patrol boat.

Later, Townsend, in a clear display of his rookie level of experience as a ship’s captain, agrees to go ashore with the mysterious escapee, named Michael Abbott, to help Abbot retrieve some personal belongings. The eventful trip ignites a fascinating story in which Lloyd weaves together four interrelated subplots against the backdrop of Civil War-era Havana.

We learn that Abbott, the rescued prison escapee, is a British private investigator who was hired to look into the mysterious death of a British diplomat in Havana that appears to have been covered up by local authorities.

While ashore, Townsend meets Emma Carpenter. The pair form a connection over a Schubert piano sonata that, over the course of the story, evolves into a sometimes tempestuous relationship.

Before returning to the Laura Ann, Townsend is attacked, separated from Abbott, knocked unconscious and awakens to find himself imprisoned in squalid conditions. After two weeks, he is visited by a mysterious Havana merchant who offers to secure Townsend’s release if Townsend agrees to be a blockade runner in support of the Confederacy.

This presents Townsend with an enormous moral dilemma. On the one hand, Townsend and his family are aligned with the Union side in the Civil War and vehemently opposed to slavery. In fact, Townsend attended the U.S. Naval academy until he was dismissed after being lured into a fight by a jealous classmate. On the other hand, Townsend is certain that he will soon die if he remains in prison. Given this Hobson’s choice, he agrees to be a blockade runner – although his moral equivocation will return when he later meets the U.S. Ambassador to Havana, himself a spy intent on turning Townsend into a double-agent working for the Union side.

The final strand in the story is Townsend’s search to figure out why his mother suddenly left Cuba as a young woman for the United States, abandoning an inheritance that included a lucrative sugar plantation.

Neither Lloyd nor his protagonist Townsend shy away from the awful reality of slavery that was the backbone of the Cuban sugar plantation economy and the central issue in the Civil War. Lloyd, through Townsend, provides vivid images of slavery’s horrors, aptly referring to the institution as something “from the devil.”

While briskly navigating those subplots, Townsend spends much of his time on various missions in the Caribbean, where he and his crew dodge screaming cannon fire, dangerous reefs and enemy ships intent on destroying the Laura Ann.

“Harbor of Spies” has plenty of adrenaline-fueled naval action as well as romance, espionage and moral dilemmas. Combined, these construct a fast-paced yet nuanced work of historical fiction based on a rock-solid foundation of exemplary research.

This is Lloyd’s second work of marine-based historical fiction; his first, “Rough Passage to London,” was published in 2013. Given Lloyd’s Maine connection and his penchant for writing about areas he knows well, one can’t help but wonder whether his next novel could be set in Maine, a place with its own storied maritime history.

Dave Canarie is a Portland attorney and an adjunct faculty member at the University of Southern Maine.

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